The Mayo Clinic has been a member of the Eastern Cooperative Oncology Group (ECOG) for 37 years. This application is submitted to request funding via the U10 mechanism to continue as a main institution member of the ECOG. Mayo Clinic faculty and affiliated institutions have participated in key scientific roles including clinical and translational studies. The Mayo Clinic is an NCI-designated Comprehensive Cancer Center that has been continuously funded since 1973. Historically, the major strengths of the Mayo Clinic Cancer Center (MCCC) have been in high quality clinical research, practice-defining clinical trials, multidisciplinary translational studies, and biostatistics. Between 1/1/04 and 12/3/08, 4,114 patients were accrued to ECOG studies by the main institution, CGOPs, and secondary CCOPs. 98 full-length manuscripts were published with Mayo or Mayo affiliate authors and 89 abstracts were presented versus 55 papers and 58 abstracts in the previous grant cycle. Major accomplishments include the following. Mayo principal investigator authorship occurred on two trials with new agents that lead to FDA-approved indications (rituximab in diffuse large B-cell lymphoma (E4494 Dr. TM Habermann) and thalidomide in multiple myeloma (E1A04 Dr. SV Rajkumar). The thrombotic risks of high-dose dexamethasone changed the practice in myeloma (E4A03 Dr SV Rajkumar). In leukemia, Dr. GW Dewald as Chair of the Cytogenetics Committee, reported that a complex karyotype confers a poor prognosis with increased risk of treatment failure in acute lymphocytic leukemia. In multiple myeloma, new biologic insights were reported in the clinical implications of t(11,14) and tumor suppressor pl6 methylation by Dr. R. Fonseca and colleagues. The specific aims are 1.) to contribute to accrual to ECOG studies as a main institution, and through CGOP programs and secondary CCOP programs, 2.) to provide clinical scientific leadership and resources to the ECOG consistent with the ECOG mission of reducing malignancy-related morbidity and mortality, 3.) to provide basic and translational scientific leadership and resources for the advancement of knowledge of the biology of malignant diseases with particular emphasis on disease-oriented expertise and/or programs unique to the Mayo Clinic, and 4.) to provide an administrative role in ECOG to support the Group's mission and goals. RELEVANCE: Participation and contributions in this mechanism have lead to new therapeutic approaches that have changed the natural history of diffuse large B-cell lymphoma and multiple myeloma improving patient survival. Biologic observations are predicting outcomes and moving to new therapeutic approaches in patients with outcomes as predicted by their presenting biology.